st: Matrix syntax with Stata 11

Dear Statalisters:
I have the following command:
matrix rownames m9 = "Foreign ownership - Treatment (i)" "Foreign ownership - Control (ii)" "Difference (i-ii)" "T-Test" "p-value"
With Stata 10, it used to work without problem.
I have received Stata 11/MP today. Now, with the same command, I get the following error message:
Foreign ownership - Treatment (i) invalid name
I apologize because I did not have time to investigate all the changes in Stata 11.
Would you have any idea?
Best regards
Herve Stolowy
***********************************************************
Professeur/Professor
HEC Paris
Departement Comptabilite Controle de gestion / Dept of Accounting and Management Control
1, rue de la Liberation
78351 - Jouy-en-Josas
France
Tel: +33 1 39 67 94 42 - Fax: +33 1 39 67 70 86
mail: stolowy at hec dot fr
web: http://www.hec.fr/stolowy
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